Chrysanthemum plant named `Sierra`

ABSTRACT

A distinct cultivar of Chrysanthemum plant named `Sierra`, characterized by its upright, uniform and rounded plant habit; large decorative disbud-type inflorescences that are 9.8 to 10.8 cm in diameter; pure white-colored ray florets; and excellent postproduction longevity with inflorescences maintaining good substance and color for about four weeks in an interior environment.

The present invention relates to a new and distinct cultivar ofChrysanthemum plant, botanically known as Dendranthema grandiflora andreferred to by the cultivar name `Sierra`.

The new cultivar is a product of a planned breeding program conducted bythe inventor in Salinas, Calif. The objective of the breeding program isto create new Chrysanthemum cultivars having inflorescences withdesirable inflorescence forms and floret colors and good post-productionlongevity.

The new cultivar originated from a cross made by the inventor inNovember, 1989, of two unnamed proprietary seedling selections.

The cultivar `Sierra` was discovered and selected by the inventor as aflowering plant within the progeny of the stated cross in a controlledenvironment in Salinas, Calif., in December, 1990. The selection of thisplant was based on its desirable inflorescence form and ray floret colorand good post-production longevity.

Asexual reproduction of the new cultivar by terminal cuttings taken in acontrolled environment in Salinas, Calif., has shown that the uniquefeatures of this new Chrysanthemum are stable and reproduced true totype in successive generations.

The cultivar `Sierra` has not been observed under all possibleenvironmental conditions. The phenotype may vary somewhat withvariations in environment such as temperature, daylength and lightintensity, without, however, any variance in genotype.

The following traits have been repeatedly observed and are determined tobe the unique characteristics of `Sierra`. These characteristics incombination distinguish `Sierra` as a new and distinct cultivar:

1. Upright, uniform and rounded plant habit.

2. Large decorative disbud-type inflorescences that are 9.8 to 10.8 cmin diameter.

3. Pure white-colored ray florets.

4. Excellent postproduction longevity with inflorescences maintaininggood substance and color for about four weeks in an interiorenvironment.

The new Chrysanthemum is similar in ray floret color to theChrysanthemum cultivar `Boaldi` (disclosed in U.S. Plant Pat. No.6,613). However in side-by-side comparisons in Salinas, Calif., undercommercial practice, plants of the new Chrysanthemum differed fromplants of the cultivar `Boaldi` in the following characteristics:

1. Plants of the new Chrysanthemum are shorter than plants of thecultivar `Boaldi.`

2. Leaves of plants of the new Chrysanthemum have divergent sinusesbetween lateral lobes whereas plants of the cultivar `Boaldi` haveparallel sinuses between lateral leaf lobes.

3. Plants of the new Chrysanthemum flower earlier than plants of thecultivar `Boaldi.`

4. Ray florets of plants of the new Chrysanthemum have a longer corollatube than ray florets of plants of the cultivar `Boaldi.`

5. Under high production temperatures, inflorescences of plants of thenew Chrysanthemum develop noninvolucral bracts whereas plants of thecultivar `Boaldi` do not develop noninvolucral bracts under highproduction temperatures.

The accompanying photographs illustrate the overall appearance of thenew cultivar.

The first sheet is a colored photograph comprising a side perspectiveview of a typical flowering plant of `Sierra`. This photograph shows thecolors as true as it is reasonably possible to obtain in coloredreproductions of this type. Floret and foliage colors in the photographmay differ from the actual colors due to light reflectance.

The second sheet is a black and white photograph comprising a topperspective view of inflorescences of the cultivar `Sierra` showing leftto right: adaxial, abaxial and lateral surfaces.

The third sheet is a black and white photograph comprising a topperspective view of the abaxial (top of photo) and adaxial (bottom ofphoto) surfaces of leaves of the cultivar `Sierra` at three differentstages of development, left to right: mature, intermediate and immature,showing the differences in size and lobation development.

In the following description, color references are made to The RoyalHorticultural Society Colour Chart except where general terms ofordinary dictionary significance are used. The following observationsand measurements describe plants grown in Leaminton, Ontario, Canada,under greenhouse conditions which approximate those generally used incommercial potted chrysanthemum production. Four unrooted cuttings weredirectly stuck in a 15-cm container. Measurements and numerical valuesrepresent averages for a minimum of four typical flowering containers.

Botanical Classification: Dendranthema grandiflora cultivar `Sierra`.

Commercial classification: Decorative disbud-type pot Chrysanthemum.

Parentage:

Male or pollen parent.--Unnamed proprietary seedling selection.

Female or see parent.--Unnamed proprietary seedling selection.

Propagation:

Type.--Terminal tip cuttings.

Time to rooting.--Seven to ten days with soil temperatures of 21C.

Rooting habit.--Fine, fibrous and well-branched.

Plant description:

Appearance.--Perennial herbaceous decorative disbud-type potChrysanthemum. Upright, uniform rounded habit and moderate branching.Four to six lateral branches develop after removal of terminal apex(pinching).

Plant height.--20 to 25 cm.

Foliage description.--Leaf arrangement: Alternate. Leaf size, fullyexpanded: Length: About 9 cm. Width: About 5 cm. Leaf apex: Acuminate.Leaf base: Attenuate. Leaf margin: Palmately lobed, sinuses betweenlateral lobes divergent. Leaf texture: Abaxial and adaxial surfacesslightly pubescent. Veins prominent on abaxial surface. Color: Youngfoliage adaxial surface: 147A. Young foliage abaxial surface: 147B.Mature foliage adaxial surface: 147A. Mature foliage abaxial surface:147B. Venation abaxial surface: 147B. Venation adaxial surface: 147B.

Inflorescence description:

Appearance.--Double decorative-type inflorescence form with pure whiteray florets. Inflorescences borne on terminals above foliage, arisingfrom leaf axils. Disk and ray florets arranged acropetally on acapitulum. Under high production temperatures, noninvolucral bracts maydevelop on the capitulum.

Flowering response.--Under natural conditions, plants flower in theautumn/winter in the Northern Hemisphere. At other times of the year,inflorescence initiation and development can be induced under shortday/long night conditions (at least 13.5 hours of darkness). Plantsexposed to 1.5 to 2 weeks of long day/short night conditions afterplanting followed by photoinductive short day/long night conditionsflower about 48 to 54 days later.

Postproduction longevity.--In an interior environment, inflorescences ofcut flowering stems will maintain good color and substance for aboutfour weeks.

Quantity of inflorescences.--As a disbud-type, all flowering stems areremoved but one to maximize inflorescence size.

Inflorescence size.--Diameter: 9.8 to 10.8 cm. Depth (height): About 1.5cm. Diameter of disc: About 4 mm.

Ray florets.--Shape: Narrowly spatulate, straight, corolla fusedapproximately 1/3 of the length of the ray florets. Size: Length: About4.5 cm. Width: About 1.5 cm. Apex: Acute. Margin: Entire. Texture:Ribbed lengthwise, smooth, glabrous. Aspect: Flat. Number of ray floretsper inflorescence: About 310. Color: Adaxial surface: 155B to 155D.Abaxial surface: 155D.

Disc florets.--Inconspicuous. Shape: Tubular. Size: Length: About 4 mm.Width: About 1 mm. Number of disc florets per inflorescence: About 16.Color: Immature: 154A. Mature: Apex: 12A. Base: White, 155D.

Peduncle.--Aspect: Strong, erect. Texture: Pubescent. Color: 143A.

Reproductive organs.--Androecium: Present on disc florets only. Anthercolor: 12A. Pollen: Little, 12A in color. Gynoecium: Present on both rayand disc florets.

Disease resistance: No known Chrysanthemum diseases observed to date onplants grown under commercial greenhouse conditions.

Seed Production: Seed production has not been observed.

It is claimed:
 1. A new and distinct cultivar of Chrysanthemum plantnamed `Sierra`, as illustrated and described.